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1.
Proc Natl Acad Sci U S A ; 121(13): e2309372121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498707

RESUMO

Renewable power generation is the key to decarbonizing the electricity system. Wind power is the fastest-growing renewable source of electricity in the United States. However, expanding wind capacity often faces local opposition, partly due to a perceived visual disamenity from large wind turbines. Here, we provide a US-wide assessment of the externality costs of wind power generation through the visibility impact on property values. To this end, we create a database on wind turbine visibility, combining information on the site and height of each utility-scale turbine having fed power into the U.S. grid, with a high-resolution elevation map to account for the underlying topography of the landscape. Building on hedonic valuation theory, we statistically estimate the impact of wind turbine visibility on home values, informed by data from the majority of home sales in the United States since 1997. We find that on average, wind turbine visibility negatively affects home values in an economically and statistically significant way in close proximity ([Formula: see text]5 miles/8 km). However, the effect diminishes over time and in distance and is indistinguishable from zero for larger distances and toward the end of our sample.

2.
Proc Natl Acad Sci U S A ; 121(14): e2313911121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527203

RESUMO

Climate change persists as a pressing global issue due to high greenhouse gas emissions from fossil fuel-based energy sources. A transition to a greener energy matrix combined with carbon offsetting is imperative to mitigate the rate at which global temperature ascends. While countries have deployed faith in green hydrogen to accelerate worldwide decarbonization efforts, the concurrent rise of blockchain-operated crypto-applications, such as bitcoin, has exacerbated climate change concerns. In this study, we propose technological solutions that combine the green hydrogen infrastructure with bitcoin mining operations to catalyze environmental and socioeconomic sustainability in climate change mitigation strategies. Since the present state of crypto-operations undeniably contributes to worldwide carbon emissions, it becomes vital to explore opportunities for harnessing the widespread enthusiasm for bitcoin as an aid toward a sustainable and climate-friendly future. Our findings reveal that green hydrogen production, paired with crypto-operations, can accelerate the deployment of solar and wind power capacities to boost conventional mitigation frameworks. Specifically, leveraging the economic potential derived from green hydrogen and bitcoin for incremental investment in renewable energy penetration, this dynamic duo can enable capacity expansions of up to 25.5% and 73.2% for solar and wind power installations. Therefore, the proposed technological solutions that leverage green hydrogen and bitcoin mining, bolstered with appropriate policy interventions, can not only strengthen renewable power generation and carbon offsetting capacities but also contribute significantly to achieving climate sustainability.

3.
Proc Natl Acad Sci U S A ; 121(25): e2313193121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38857390

RESUMO

Renewable Portfolio Standards (RPSs) are one of the most prevalent and impactful clean energy policies implemented by states in the United States. This paper investigates the regional spillover effect of RPS policies using a directed dyad panel dataset of renewable electricity generation in US states from 1991 to 2021. Regional spillover effect is measured in two ways: by considering the influence of an RPS enacted in neighboring states and in states in the same regional transmission organization or independent system operator region. We use dyadic fixed effects estimation and conclude that the neighboring state's RPS stringency score is a strong determinant of a state's total renewable electricity generation. For states without an RPS, the positive influence of an RPS in a neighboring state is larger when the non-RPS state has more abundant renewable energy resources than the neighboring RPS state. Our findings suggest that past RPS policy evaluation research using a confined within-state focus may have underestimated the holistic impact of an RPS, as the impacts of an RPS policy can extend beyond the enacting state's borders. Overall, this study contributes to an improved understanding of the holistic impact of state RPS policies.

4.
Proc Natl Acad Sci U S A ; 121(10): e2306517121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408236

RESUMO

China has committed to achieve net carbon neutrality by 2060 to combat global climate change, which will require unprecedented deployment of negative emissions technologies, renewable energies (RE), and complementary infrastructure. At terawatt-scale deployment, land use limitations interact with operational and economic features of power systems. To address this, we developed a spatially resolved resource assessment and power systems planning optimization that models a full year of power system operations, sub-provincial RE siting criteria, and transmission connections. Our modeling results show that wind and solar must be expanded to 2,000 to 3,900 GW each, with one plausible pathway leading to 300 GW/yr combined annual additions in 2046 to 2060, a three-fold increase from today. Over 80% of solar and 55% of wind is constructed within 100 km of major load centers when accounting for current policies regarding land use. Large-scale low-carbon systems must balance key trade-offs in land use, RE resource quality, grid integration, and costs. Under more restrictive RE siting policies, at least 740 GW of distributed solar would become economically feasible in regions with high demand, where utility-scale deployment is limited by competition with agricultural land. Effective planning and policy formulation are necessary to achieve China's climate goals.

5.
Nature ; 629(8012): 507, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38714907
6.
Nature ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020185
7.
Nature ; 632(8024): 240-241, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39054365
10.
Nature ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297046
12.
Nature ; 632(8024): 231, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39107414
13.
Nature ; 625(7994): 241, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38195870
14.
Nature ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38653832
15.
Nano Lett ; 24(30): 9147-9154, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39028759

RESUMO

Photoenhanced batteries, where light improves the electrochemical performance of batteries, have gained much interest. Recent reports suggest that light-to-heat conversion can also play an important role. In this work, we study Prussian blue analogues (PBAs), which are known to have a high photothermal heating efficiency and can be used as cathodes for Li-ion batteries. PBAs were synthesized directly on a carbon collector electrode and tested under different thermally controlled conditions to show the effect of photothermal heating on battery performance. Our PBA electrodes reach temperatures that are 14% higher than reference electrodes using a blue LED, and a capacity enhancement of 38% was achieved at a current density of 1600 mA g-1. Additionally, these batteries show excellent cycling stability with a capacity retention of 96.6% in dark conditions and 94.8% in light over 100 cycles. Overall, this work shows new insights into the effects leading to improved battery performance in photobatteries.

16.
Biotechnol Bioeng ; 121(3): 894-902, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38164703

RESUMO

Biodiesel has the potential to serve as a feasible substitute for fossil fuels in many sectors, including transportation and internal combustion engines, without requiring extensive modifications. UsinHemg alternative energy sources, including biodiesel, is necessary to effectively tackle the growing demand predominantly observed in the transportation sector. This review is aimed to examine the technological progress, potential benefits, obstacles, and prospects associated with using biodiesel in India. India exhibits a significant potential for biodiesel production due to the abundance of various biofuel crops within its territory. The information supplied includes recent information from official government reports and literature. Collaborative efforts among all stakeholders in the energy industry can achieve the realization of reducing imports of petroleum-based fuel. However, it is essential to consider several significant elements specific to the Indian context when considering the utilization of biodiesel. The reported findings in this research are expected to shed light on the current and prospects of biodiesel deployment in India.


Assuntos
Biocombustíveis , Gasolina , Produtos Agrícolas , Índia
17.
Chem Rec ; 24(5): e202400016, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38775239

RESUMO

Hydrogen gas is a prominent focus in pursuing renewable and clean alternative energy sources. The quest for maximizing hydrogen production yield involves the exploration of an ideal photocatalyst and the development of a simple, cost-effective technique for its generation. Iron titanate has garnered attention in this context due to its photocatalytic properties, affordability, and non-toxic nature. Over the years, different synthesis routes, different morphologies, and some modifications of iron titanate have been carried out to improve its photocatalytic performance by enhancing light absorption in the visible region, boosting charge carrier transfer, and decreasing recombination of electrons and holes. The use of iron titanate photocatalyst for hydrogen evolution reaction has seen an upward trend in recent times, and based on available findings, more can be done to improve the performance. This review paper provides a comprehensive overview of the fundamental principles of photocatalysis for hydrogen generation, encompassing the synthesis, morphology, and application of iron titanate-based photocatalysts. The discussion delves into the limitations of current methodologies and present and future perspectives for advancing iron titanate photocatalysts. By addressing these limitations and contemplating future directions, the aim is to enhance the properties of materials fabricated for photocatalytic water splitting.

18.
Chem Rec ; 24(3): e202300308, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38200590

RESUMO

The transition to sustainable transportation has fueled the need for innovative electric vehicle (EV) charging solutions. Building Integrated Photovoltaics (BIPV) systems have emerged as a promising technology that combines renewable energy generation with the infra-structure of buildings. This paper comprehensively reviews the BIPV system for EV charging, focusing on its technology, application, and performance. The review identifies the gaps in the existing literature, emphasizing the need for a thorough examination of BIPV systems in the context of EV charging. A detailed review of BIPV technology and its application in EV charging is presented, covering aspects such as the generation of solar cell technology, BIPV system installation, design options and influencing factors. Furthermore, the review examines the performance of BIPV systems for EV charging, focusing on energy, economic, and environmental parameters and their comparison with previous studies. Additionally, the paper explores current trends in energy management for BIPV and EV charging, highlighting the need for effective integration and recommending strategies to optimize energy utilization. Combining BIPV with EV charging provides a promising approach to power EV chargers, enhances building energy efficiency, optimizes the building space, reduces energy losses, and decreases grid dependence. Utilizing BIPV-generated electricity for EV charging provides electricity and fuel savings, offers financial incentives, and increases the market value of the building infrastructure. It significantly lowers greenhouse gas emissions associated with grid and vehicle emissions. It creates a closed-loop circular economic system where energy is produced, consumed, and stored within the building. The paper underscores the importance of effective integration between Building Integrated Photovoltaics (BIPV) and Electric Vehicle (EV) charging, emphasizing the necessity of innovative grid technologies, energy storage solutions, and demand-response energy management strategies to overcome diverse challenges. Overall, the study contributes to the knowledge of BIPV systems for EV charging by presenting practical energy management, effectiveness and sustainability implications. It serves as a valuable resource for researchers, practitioners, and policymakers working towards sustainable transportation and energy systems.

19.
Environ Sci Technol ; 58(12): 5187-5195, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38490225

RESUMO

Clean hydrogen has the potential to serve as an energy carrier and feedstock in decarbonizing energy systems, especially in "hard-to-abate" sectors. Although many countries have implemented policies to promote electrolytic hydrogen development, the impact of these measures on costs of production and greenhouse gas emissions remains unclear. Our study conducts an integrated analysis of provincial levelized costs and life cycle greenhouse gas emissions for all hydrogen production types in China. We find that subsidies are critical to accelerate low carbon electrolytic hydrogen development. Subsidies on renewable-based hydrogen provide cost-effective carbon dioxide equivalent (CO2e) emission reductions. However, subsidies on grid-based hydrogen increase CO2e emissions even compared with coal-based hydrogen because grid electricity in China still relies heavily on coal power and likely will beyond 2030. In fact, CO2e emissions from grid-based hydrogen may increase further if China continues to approve new coal power plants. The levelized costs of renewable energy-based electrolytic hydrogen vary among provinces. Transporting renewable-based hydrogen through pipelines from low- to high-cost production regions reduces the national average levelized cost of renewables-based hydrogen but may increase the risk of hydrogen leakage and the resulting indirect warming effects. Our findings emphasize that policy and economic support for nonfossil electrolytic hydrogen is critical to avoid an increase in CO2e emissions as hydrogen use rises during a clean energy transition.


Assuntos
Gases de Efeito Estufa , Carvão Mineral , Efeito Estufa , Hidrogênio , Centrais Elétricas , Dióxido de Carbono/análise
20.
Environ Sci Technol ; 58(26): 11247-11255, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38904766

RESUMO

Companies are increasingly relying on emission reductions attributable to their adoption of renewable electricity to achieve net-zero emission targets. However, there is a risk of double counting of emission reductions threatening the credibility of corporate climate actions due to defective accounting rules of GHG emissions related to electricity consumption and the overlap between different market-based instruments, including carbon credit markets, renewable power purchase agreements, and renewable energy certificates. Using data of 63 major Chinese companies in seven sectors, we quantitatively assess the risks of double counting related to corporate sourcing of renewables and their consequent influences on the alignment of corporate emission trajectories with the 1.5 °C goal of the Paris Agreement. Results show that 7.1% of the electricity consumed by sample companies in 2021 was from renewable energy procurement and deployment, with which they reported 8.27 Mt of CO2e emission reductions compared to the scenario with no renewable electricity consumption. However, emission reductions that could be double counted are predicted to be 0.9-1.3 times as many as emission reductions that companies will report during 2021-2030. After adjustment of the reported emissions that might be underestimated due to double counting, the overall emission trajectories of sample companies are no longer aligned with the 1.5 °C goal. Our findings suggest that it is urgently needed to improve the corporate carbon accounting rules and increase the transparency of corporate carbon disclosures.


Assuntos
Gases de Efeito Estufa , Eletricidade , Energia Renovável
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